diff --git a/src/runner_doiact_vec.c b/src/runner_doiact_vec.c
index 7e9263ad7e408941984a358f36acd393e7b70c64..127c9aa168428748baf4c46f1361b0ef447f1887 100644
--- a/src/runner_doiact_vec.c
+++ b/src/runner_doiact_vec.c
@@ -304,6 +304,8 @@ __attribute__((always_inline)) INLINE void runner_doself1_density_vec(
   int count_align;
   int num_vec_proc = NUM_VEC_PROC;
 
+  int intCount = 0;
+
   struct part *restrict parts = c->parts;
   const int count = c->count;
 
@@ -526,10 +528,14 @@ __attribute__((always_inline)) INLINE void runner_doself1_density_vec(
     VEC_HADD(curlvySum, pi->density.rot_v[1]);
     VEC_HADD(curlvzSum, pi->density.rot_v[2]);
 
+    intCount += icount;
+
     /* Reset interaction count. */
     icount = 0;
   } /* loop over all particles. */
 
+  message("Total number of self interactions: %d, average per particle: %f.", intCount, ((float)intCount) / ((float)count));
+  
   TIMER_TOC(timer_doself_density);
 #endif /* WITH_VECTORIZATION */
 }